Injection pump for diesel engines



2 Sheet-Sheet l ALDER INJECTION PUMP FOR DIESEL ENGINES Filed om. 20. 1930 /NVE/VTOR. STANLEY AL DER.-

m E N m T T A Nov. 8, 1932.

Nov. 8, 1932'. s, ALDER 1,886,930

INJECTION PUMP FOR DIESEL ENGINES Filed Occ 20, 19:50 2 Sheets-Sheet 2' FIGB.

luvsmon.

ATTORNE! Patented Nov. 1932 J UNITED STATES PATENT OFFICE STANLEY ALDER, OI BOKEB, SUNDERLAN D, ENGLAND INJECTION PUMP FOR DIESEL ENGINES Application filed October 20, 1930, Serial No. 490,069, and in Great Britain October 22, 1929.

\ This invention relates to fuel injection pumps for Diesel engines and the like of the type in which capacity is varied by relatively rotating the piston and a sleeve in which the piston is guided, and has for its object to provide an improved pump control means iving a more delicate control than hitherto, w ile at the same time giving a quicker cut d with a larger eflective stroke for the same move- 510 ment of the plunger as hitherto. Another object of the invention is to provide means for inde ndently adjustin each unit of a multi-cy inder pump. A urther object of the invention is to provide means whereby the moving parts may be quickly removed when desired.

According to the resent invention, means are provided for e ecting relative rotation between the plunger and sleeve up to 360, while the sleeve has an inclined edge extendin up to 360 and cooperating wlth a plura it of release apertures in the plun er whic apertures are arran ed along a he ix corresponding with the inc ined edge on the sleeve.

With this arrangement the several apertures are uncovered simultaneously, thus 'ving a more rapidinitial fall in pressure t an 80 area is equal to the sum of the areas of the apertures in the present invention. Then ain, each aperture is preferably a fraction 3% the area of the plunger bore, so that its diameter is lessthan where one aperture is used, and as a result it requires less travel of the plunger to cover and uncover it. Hence the effective stroke of the plunger is increased.

The incoming fuel oil is led to the plunger through one passage, while the rejected fuel oil is led away by a separate passage so that there is no mixing of the two, and a fuel charge of unvarying consistency is thus always provided.

2 is a plan view partly in section, and Fig. 3

The invention will now be described with A is an elevational view partly in section showing means for adjustment of the racks.

The plunger B, pump liner C and rotatable guide or sleeve D with helical end, together with the plungers return-spring E and abutment washer F are all assembled within a housing G, the pump liner C being extended to embrace the rotatable sleeve D in order to ensure correct alignment of these parts with thebore of the pump.

This whole internal assemblage may be withdrawn from the housing G by unscrewing the clam ing nut H, and removing the ad usting rac P.

The drawings (Fig. 1) also show the nonreturn discharge valve J and its spring, the oil inlet ports K and inlet belt L the oil release ports M and oil release belt ll.

The axis of the toothed rack P is placed transversel to the axis of the cam shaft and m each rotata le guide has its own rack, so that independent adjustment of each unit of the multi-cylinder pump may-be efiected. Figs.

2 and 3 illustrate an example of adjustable connection of the racks P to a common cross bar X, the said racks being screw threaded at their ends to engage with adjusting nuts U carrying lock-nuts T. Adjustment is efiectis possible with a single aperture whose ed by turnin a nut U until its res ective rack P has turne the sleeve D to the esired posi- $0 tion, and then looking by means of the nut T. The ends of the cross bar X engage in slots in the end of arms V, V on the end of the control shaft W. The engine throttle is connected to the several racks. The rack engages with teeth out on the external surface of the rotatable guide D.

The plunger has one relief duct R drilled along its axis and terminating in smaller holes S, the axes of which lie along a helix of W the same pitch as that of the helical ed e of the guide D, thus ensuring that they will be uncovered simultaneously by the said helical edge as the plunger B reciprocates.-

The lunger B is formed with two diameters, t e upper part being kept to a small diameter suitable for the required displacement of oil needed for engine, injection, while the lower part, which is surrounded by the sleeve, is of more robust construction on 8.0-

count of the weakenin effect of the radial plunger, a sprin between said abutment and holes.

The increased iameter of the lower said sleeve, an

portion of the lunger B also resents a largadapted to hold said liner in said housing.

er wearing sur ace to the gui e sleeve.

In witness whereof I have signed this speci- The action of the pump is as follows :In fication.

the downward movement of the lunger B incoming fuel oil enters throu h tlie port K. In the first art of the u war the plunger the oil is orced past the valve J into the cylinder. In the latter art of the upward movement of the plunger the position of the guide D havin been adjusted by movement of the rack P, t e small transverse holes in the plun er are uncovered by the edge of the helix as t ey emerge from the gui e,

, and the oil under compression in the pump free to esca e by way of the ducts R an into the oil elt N, and thence to the supply tank. a

I claim 1. A fuel injection ump comprising a pump housing, a pump c amber in said housmg, a pump lnlet communicatin with said pump chamber, a sleeve in said ousin an inclined edge on sand sleeve, a plunger a apt ed to reciprocate in said sleeve and in said pump chamber, acentral bore in said plunger, said bore opening at one end into said ump chamber, a pump by-pass in said pump ousmg, a plurality of release a ertures in said plunger communicating wit said bore on the one hand and said pump outlet on the other hand, said apertures being arranged responding with sai along a helix corresponding with said inclined edge and adapted to cooperate with.

said inclined edge to effect the fuel release, and means for efi'ectin relative rotation up to 360 between said p unger and sleeve.

2.'A fuel injection pump. according to claim 1, wherein the release apertures in the plunger are arranged at equal distances around the periphery of the plunger.

3. A fuel injection ump according to claim 1, wherein the total cross sectional area of the release apertures is at least equal to that of the bore of the plunger.

4. A fuel injection pump. comprising a pump housing,'a pump iner in sai housing, a pump chamber in said liner, a pump inlet communicatin with said pump chamber, a sleeve in said finer, an inclined edge on said sleeve a plun or adapted to reci rocate in said s eeve an in the pump cham er, acentral bore in said plunger, said bore opening at one end intosald pump chamber, a pump by-pass in said pump liner,'a plurality of release apertures in said plunger communicating with said bore on theone hand and said pump by-pass onthe other hand, said apertures being arran ed along a helix corinclined edge and adapted to cooperate with said inclined edge to efiect the fuel release, means for eflectin relative rotation up to 360 between sai plunger and sleeve, an abutment on said movement of STANLEY ALDER.

a screw threaded member 

